The instant application is the national phase application filed under 35 USC xc2xa7371 of PCT/EP96/02672 filed on Jun. 20, 1996.
The present invention relates to novel plant-protecting active ingredient mixtures having synergistically enhanced action, comprising at least two active ingredient components together with a suitable carrier, wherein component I is a compound having plant-immunising action of formula I 
wherein
Z is CN, COOH or a salt thereof, COxe2x80x94OC1-C4alkyl or COxe2x80x94SC1-C4alkyl;
and wherein component II is a compound having microbicidal action selected from the group
A) xcex1-[2-(4-chlorophenyl)ethyl]-xcex1-(1,1-dimethylethyl)-1H-1,2,4-trazole-1-ethanol, (xe2x80x9ctebuconazolxe2x80x9d), (reference: EP-A40 345);
B) 1-[[3-(2-chlorophenyl)-2-(4-fluorophenyl)oxiran-2-yl]methyl]-1H-1,2,4-triazole, (xe2x80x9cepoxyconazolxe2x80x9d), (reference: EP-A-196 038);
C) xcex1-(4-chlorophenyl)-xcex1-(1 -cyclopropylethyl)-1H-1,2,4-triazole-1-ethanol, (xe2x80x9ccyproconazolxe2x80x9d), (reference: U.S. Pat. No. 4,664,696);
D) 5-(4-chlorobenzyl)-2,2-dimethyl-1-(1H-1,2,4-triazol-1-ylmethyl)-cyclopentanol, (xe2x80x9cmetconazolxe2x80x9d), (reference: EP-A-267 778);
E) 2-(2,4-dichlorophenyl)-3-(1H-1,2,4-triazol-1-yl)propyl-1,1,2,2-tetrafluoroethyl ether, (xe2x80x9ctetraconazolxe2x80x9d), (reference: EP-A-234 242);
F) methyl-(E)-2-{2-[6-(2-cyanophenoxy)pyrimidin4-yloxy]phenyl}-3-methoxyacrylate, (xe2x80x9cICI A 5504xe2x80x9d, xe2x80x9cazoxystrobinxe2x80x9d), (reference: EP-A-382 375);
G) methyl-(E)-2-methoximino-2-[xcex1-(o-tolyloxy)-o-tolyl]acetate, (xe2x80x9cBAS 490 Fxe2x80x9d, xe2x80x9ccresoxime methylxe2x80x9d), (reference: EP-A-400 417);
H) 2-(2-phenoxyphenyl)-(E)-2-methoximino-N-methylacetamide, (reference: EP-A-398 692);
J) [2-(2,5-dimethylphenoxymethyl)-phenyl]-(E)-2-methoximino-N-methylacetamide, (reference: EP-A-398 692);
K) (1R,3S/1S,3R)-2,2-dichloro-N-[(R)-1-(4-chlorophenyl)ethyl]-1-ethyl-3-methylcyclo-propanecarboxamide, (xe2x80x9cKTU 3616xe2x80x9d), (reference: EP-A-341 475); and
L) manganese ethylenebis (dithiocarbamate) polymer-zinc complex, (xe2x80x9cmancozebxe2x80x9d); (reference: U.S. Pat. No. 2,974,156).
The invention relates also to salts and metal complexes of compounds I and II.
Of the compounds of formula I, preference is given to those wherein Z is COOH (compound IA) or a salt thereof, CN (compound IB), COOCH3 (compound IC) or COSCH3 (compound ID).
Preferred salts are alkali metal and alkaline earth metal salts, especially lithium, sodium, potassium, magnesium or calcium salts, and also organic salts, especially salts of salt-forming amines, for example trimethylamine, triethylamine, N,N-dimethylaniline, pyridine, triethanolamine, morpholine.
Very special preference is given to the compound of formula I wherein Z is COSCH3 (compound ID).
It is known that compounds of formula I activate the plant""s own latent defence system against pathogenic microbial influences and accordingly are able to protect the plant against pathogens (EP-A-313 512).
At low rates of application those compounds have no direct action on the noxious organisms, but they immunise the healthy plant against diseases.
The disadvantage in using compounds of formula I to control plant diseases is that the action is often inadequate at low rates of application.
Surprisingly, it has now been found that compounds of formula I in admixture with one of the conventional microbicides IIA to IIL have synergistically enhanced action. Using such mixtures it is possible to control plant diseases on the one hand by strengthening the plant by activating its own defence system and on the other hand by additionally controlling the pathogens directly. Compared with the customary methods of controlling plant diseases, unexpectedly small amounts of active ingredients are required.
A particular advantage of the mixtures according to the invention is further that, because the modes of action of components I and II are completely different, the threat of resistance being developed in the control of plant diseases is effectively prevented.
The synergistically enhanced action of mixtures of components I and II manifests itself, for example, in lower rates of application, a longer duration of action and altogether higher crop yields. Such enhancements were not to be expected from the sum of the actions of the individual components.
The present invention relates also to a method of protecting plants against plant diseases, especially against fungus infestation, by treating the plants, parts of the plants or their surroundings with a component I and a component II in any desired sequence or simultaneously.
Advantageous mixing ratios of the two active ingredients are I:II=from 1:30 to 10:1, preferably I:II=from 1:20 to 2:1 and from 1:10 to 1:1.
Especially advantageous mixing ratios are further for I:IIK, from 1:1 to 100:1, preferably from 1:1 to 10:1; and for I:IIL, from 1:10 to 1:100, preferably from 1:10 to 1:50.
The active ingredient mixtures I+II according to the invention have very advantageous properties for protecting plants against disease infestation.
The active ingredient mixtures of the invention can be used to inhibit or destroy the microorganisms which occur on plants or on parts of plants (the fruit, blossom, leaves, stems, tubers or roots) of different crops of useful plants, while at the same time parts of plants that grow later are also protected against such microorganisms. They can also be used as dressings in the treatment of plant propagation material, especially seed (fruit, tubers, grains) and plant cuttings (e.g. rice), to provide protection against fungus infections as well as against phytopathogenic fungi which occur in the soil The active ingredient mixtures according to the invention are distinguished by the fact that they are especially well tolerated by plants and are environmentally friendly.
The active ingredient mixtures are effective against phytopathogenic fungi belonging to the following classes: Ascomycetes (e.g. Venturia, Podosphaera, Erysiphe, Monilinia, Mycosphaerella, Uncinula); Basidiomycetes (e.g. the genus Hemileia, Rhizoctonia, Puccinia); Fungi imperfecti (e.g. Botrytis, Helminthosporium, Rhynchosporum, Fusarium, Septoria, Cercospora, Altemaria, Pyricularia and, especially, Pseudocercosporella herpotrchoides); Oomycetes (e.g. Phytophthora, Peronospora, Bremia, Pythium, Plasmopara).
Target crops for the areas of indication disclosed herein comprise within the scope of the present invention e.g. the following species of plants: cereals (wheat, barley, rye, oats, rice, sorghum and related crops); beet (sugar beet and fodder beet); pomes, stone fruit and soft fruit (apples, pears, plums, peaches, almonds, cherries, strawberries, raspberries and black-berries); leguminous plants (beans, lentils, peas, soybeans); oil plants (rape, mustard, poppy, olives, sunflowers, coconut, castor oil plants, cocoa beans, groundnuts); cucumber plants (marrows, cucumber, melons); fibre plants (cotton, flax, hemp, jute); citrus fruit (oranges, lemons, grapefruit, mandarins); vegetables (spinach, lettuce, asparagus, cabbages, carrots, onions, tomatoes, potatoes, paprika); lauraceae (avocados, cinnamon, camphor); or plants such as maize, tobacco, nuts, coffee, sugar cane, tea, vines, hops, bananas and natural rubber plants, as well as omamentals (flowers, shrubs, broad-leaved trees and evergreens, such as conifers). This list does not represent any limitation.
The active ingredient mixtures according to the invention are especially advantageous for use in cereals, more especially in wheat; also in potatoes, vines, lawn areas, hops, tobacco, bananas and vegetables. The mixtures I+IIK are especially suitable for the treatment of rice, and the mixtures I+IIL are especially suitable for fruits, fruit and vegetables.
The mixtures of active ingredients of formulae I and II are generally used in the form of compositions. The active ingredients of formulae I and II can be applied to the area or plant to be treated either simultaneously or in succession on the same day, if desired together with further carriers, surfactants or other application-promoting adjuvants customarily employed in formulation technology.
Suitable carriers and adjuvants can be solid or liquid and are the substances ordinarily employed in formulation technology, e.g. natural or regenerated mineral substances, solvents, dispersants, wetting agents, tackifiers, thickeners, binders or fertilisers.
A preferred method of applying an active ingredient mixture comprising at least one of each of the active ingredients I and II is application to the parts of the plants that are above the soil, especially to the leaves (foliar application). The frequency and rate of application depend upon the biological and climatic living conditions of the pathogen. The active ingredients can, however, also penetrate the plant through the roots via the soil or via the water (systemic action) if the locus of the plant is impregnated with a liquid formulation (e.g. in rice culture) or if the substances are introduced in solid form into the soil, e.g. in the form of granules (soil application). In order to treat seed, the compounds of formulae I and II can also be applied to the seeds (coating), either by impregnating the tubers or grains with a liquid formulation of each of the active ingredients in succession, or by coating them with an already combined wet or dry formulation. In addition, in special cases, other methods of application to plants are possible, for example treatment directed at the buds or the fruit trusses.
The compounds of the combination are used in unmodified form or, preferably, together with the adjuvants conventionally employed in formulation technology, and are therefore formulated in known manner e.g. into emulsifiable concentrates, coatable pastes, directly sprayable or dilutable solutions, dilute emulsions, wettable powders, soluble powders, dusts, granules, or by encapsulation in e.g. polymer substances. As with the nature of the compositions, the methods of application, such as spraying, atomising, dusting, scattering, coating or pouring, are chosen in accordance with the intended objectives and the prevailing circumstances. Advantageous rates of application of the active ingredient mixture are normally from 50 g to 2 kg a.i./ha, preferably from 100 g to 1000 g a.i./ha, especially from 150 g to 700 g a.i./ha. In the case of the treatment of seed, the rates of application are from 0.5 g to 1000 g, preferably from 5 g to 100 g, a.i. per 100 kg of seed.
The formulations are prepared in known manner, e.g. by homogeneously mixing and/or grinding the active ingredients with extenders, e.g. solvents, solid carriers and, where appropriate, surface-active compounds (surfactants).
Suitable solvents are: aromatic hydrocarbons, preferably the fractions containing 8 to 12 carbon atoms, e.g. xylene mixtures or substituted naphthalenes, phthalates, such as dibutyl phthalate or dioctyl phthalate, aliphatic hydrocarbons, such as cyclohexane or paraffins, alcohols and glycols and their ethers and esters, such as ethanol, ethylene glycol, ethylene glycol monomethyl or monoethyl ether, ketones, such as cyclohexanone, strongly polar solvents, such as N-methyl-2-pyrrolidone, dimethyl sulfoxide or dimethylformamide, as well as vegetable oils or epoxidised vegetable oils, such as epoxidised coconut oil or soybean oil; or water.
The solid carriers used, e.g. for dusts and dispersible powders, are normally natural mineral fillers, such as calcite, talcum, kaolin, montmorillonite or attapulgite. In order to improve the physical properties it is also possible to add highly dispersed silicic acid or highly dispersed absorbent polymers. Suitable granulated adsorptive carriers are porous types, for example pumice, broken brick, sepiolite or bentonite, and suitable nonsorbent carriers are, for example, calcite or sand. In addition, a great number of pregranulated materials of inorganic or organic nature can be used, e.g. especially dolomite or pulvensed plant residues.
Depending upon the nature of the active ingredients of formulae I and II to be formulated, suitable surface-active compounds are non-ionic, cationic and/or anionic surfactants having good emulsifying, dispersing and wetting properties. The term xe2x80x9csurfactantsxe2x80x9d will also be understood as comprising mixtures of surfactants.
Particularly advantageous application-promoting adjuvants are also natural or synthetic phospholipids of the cephalin and lecithin series, e.g. phosphatidylethanolamine, phosphatidylserine, phosphatidylglycerol and lysolecithin.
The agrochemical compositions generally comprise 0.1 to 99%, preferably 0.1 to 95%, of active ingredients of formulae I and II, 99.9 to 1%, preferably 99.9 to 5%, of a solid or liquid adjuvant and 0 to 25%, preferably 0.1 to 25%, of a surfactant.
Whereas commercial products will preferably be formulated as concentrates, the end user will normally employ dilute formulations.